Biopsy or No Biopsy
Standard TRUS Biopsy
Biopsy is the only way to find out for sure if a man has prostate cancer. Standard prostate biopsy is usually done with an ultrasound and a probe. The man has to have an enema (usually a Fleets enema which is an over the counter product ). Antibiotics are given for several days before and after the biopsy. Infectious complications are less when the patient gets an IV or IM injection of antibiotic before the biopsy. Alternatively some doctors will culture the rectal flora with a swab test several days before the procedure. This swab testing is time consuming and most urologists are not doing it.
The trans rectal biopsy procedure is usually done under local anesthesia. For the procedure the man will lie on his side and the probe goes into the rectum.Some physicians will instil some lidocaine jelly into the rectum prior to placing the probe
First, a picture of the prostate is obtained using ultrasound. The prostate gland's size, shape and any abnormalities are noted. The most common abnormalities are dark or “hypoechoic areas”, which may be prostate cancer. But not all prostate cancers can be seen. And not all hypoechoic areas are cancer.
The prostate gland is then anesthetized through a thin needle passed through the probe. The doctor then removes a very thin barely visible slice of prostate tissue about ¾ inch long and 1/16 inch wide. Usually 6-12 biopsies are performed. The number depends on the size of the prostate gland, PSA test results, and past biopsies. During an extended biopsy procedure 18 or 24 samples are taken.
The biopsy takes 10 to 20 minutes. A pathologist, a doctor who specialises in study of cancerous tissue will examine the the biopsy tissue. The pathologist will determine if there is cancer. The report may take several days depending on the special stains and processing that may be required. Sometimes tissue is sent to a university center for a second opinion
The report usually details the length of cancer in the sample as a percent of its total length,the grade of cancer and other details
A trans perineal, saturation, template or 3 D biopsy is carried out with the man under general anaesthesia. The positioning is usually in lithotomy (like a gyn exam)
Men are given intravenous prophylactic antibiotic coverage and a temporary urinary catheter is placed after the man is asleep. A grid template with multiple holes approximately 5 mm apart is placed on the perineum (area under the scrotum). Under transrectal ultrasound guidance a biopsy needle is introduced through different holes in the template,and through the skin to obtain biopsies from defined parts of the prostate.
Template biopsy allows a large number of tissue samples to be obtained from different parts of the prostate. This may improve detection of small cancers compared with other biopsy methods. Transperineal technique also causes less infection as needles are not introduced through the rectum. It avoids missing samples from the anterior area (the top portion of prostate usually not reached by transrectal needles) and portions of prostate around the urethra the areas which contribute from a fourth to half of all prostate cancer (which are also often missed by conventional TRUS biopsies).
Nevertheless, this procedure also comes with potential side-effects.Anesthetic complications are risks of any anesthetic which include cardiac or breathing issues, aspiration pneumonia and others.Pain in the perineal region is a side effect unique to perineal biopsy in a few men.Younger patients reported a higher incidence of pain in the perineal area after a template biopsy is performed, irrespective of the number of biopsies taken.
Template biopsies also need specialised equipment, biplanar rectal probe, the biopsy grid, and an expensive probe holder. There is also a learning curve for the urologist as he is not used to performing this routinely unless he does radiation seed placements routinely
STANDARD BIOPSY TECHNIQUES ARE INACCURATE TO
DIAGNOSE PROSTATE CANCER
A finding of elevated PSA or abnormal DRE is only the first step in the diagnostic pathway. Until recently the next step was always a biopsy. There are now some additional tests that will help avoid biopsy in many patients. However not all urologists are convinced or feel comfortable about using these tests to postpone or avoid biopsy. About a third of urologists who are experts in prostate cancer and have fellowship training and specialise in prostate cancer will recommend additional tests before performing a biopsy. The most commonly used newer tests before a biopsy are the 4K test and multiparametric MRI. These tests will help to decide whether a man needs a biopsy or not and is discussed in detail in the next few pages.
There are several types of biopsy that can be used to detect prostate cancer. They include the standard,extended, template guided, saturation or 3D biopsy techniques.
The most recent addition is the MRI guided fusion biopsy.
An elevated PSA is only the first step in the diagnostic pathway.The next step is a biopsy. Standard biopsy techniques are inaccurate in diagnosis of prostate cancer.
There are several inherent flaws associated with standard TRUS biopsy. Because these biopsies are done without specific targeting of of cancerous areas there is under detection, over detection and misclassification of cancer.
Trus biopsies have a high false negative rate because standard TRUS biopsy will miss cancers that are significant. This is called under detection. This leads to delayed diagnosis, repeat biopsies due to rising PSA, increased morbidity, escalating costs and more intense therapy of larger, more advanced cancers with increased side effects and loss of quality of life
Standard TRUS biopsies misclassify cancer grade and stage leading to delayed diagnosis and erroneous treatment
TRUS biopsies detect a high number of latent insignificant, low grade cancers that should not be detected as they pose no threat to life. This is called over detection. Overdetection leads to overtreatment,increased morbidity, escalating costs and loss of quality of life
After any type of prostate biopsy, men may have blood in the ejaculate, urine and stool. This stops within a few days for urine and a few weeks for semen.. Men will need to take an antibiotic for several days after the biopsy. Infections are uncommon with trans perineal biopsies http://www.urologyhealth.org